Role Of Verbal Working Memory Research Articles

Production of Sentential Negation in German and Italian Non-fluent Aphasia

The ability of persons with non-fluent aphasia (PWAs) to produce sentential negation has been investigated in several languages, but only in small samples. Accounts of (morpho)syntactic impairment in PWAs have emphasized various factors, such as whether the negative marker blocks or interferes with verb movement, the position of the Negation Phrase in the syntactic hierarchy or the interpretability of negation. This study investigates the ability of German- and Italian-speaking PWAs to construct negative sentences, as well as the role of verbal working memory (WM) capacity and education in task performance and production of sentential negation. German and Italian differ in the syntactic properties of the negative markers that are relevant here (nicht and non, respectively). A sentence anagram task tapping into the construction of negative and affirmative declarative sentences was administered to 9 German- and 7 Italian-speaking PWAs, and to 14 German- and 11 Italian-speaking age- and education-matched healthy volunteers. We fitted generalized linear mixed-effects models to the datasets. There was no significant difference between negative and affirmative sentences in either group of PWAs. There was a main effect of verbal WM capacity on task performance, but no interaction between verbal WM capacity and production of negative vs. affirmative sentences. Education did not affect task performance. The results are discussed in light of different linguistically-informed accounts of (morpho)syntactic impairment in non-fluent aphasia.

The Critical Role of Semantic Working Memory in Language Comprehension and Production

Although research on the role of verbal working memory (WM) in language processing has focused on phonological maintenance, considerable evidence indicates that the maintenance of semantic information plays a more critical role. This article reviews studies of brain-damaged and healthy individuals demonstrating the contribution of semantic WM to language processing. On the sentence-comprehension side, semantic WM supports the retention of individual word meanings prior to their integration. It also serves to maintain semantic information in an activated state such that semantic interference between sentence constituents can be resolved. Phonological WM does not appear to support either of these functions, though it contributes to verbatim sentence recall. On the production side, evidence points to the phrase as the minimal scope of advance planning in sentence formulation, and to semantic WM as supporting the representation of the meanings of the content words within a phrase. Planning at the phonological level appears to have a very limited scope, making few demands on phonological WM. These findings imply that treatment of semantic but not phonological WM deficits should lead to improved sentence comprehension and production, and preliminary findings support that view.

Working memory and fluid intelligence predict reading comprehension in school‐age children: A one‐year longitudinal study

SummaryThe present study analyzed the joint predictive role of verbal working memory (WM), verbal short‐term memory (STM), fluid intelligence, and intelligence mindset in reading comprehension, controlling for prior reading comprehension performance, in typically developing Spanish‐speaking school‐aged children. A sample of 83 children aged 9–10 years old were evaluated at fourth grade of primary school, with measures of verbal WM, verbal STM, fluid intelligence, intelligence mindset and reading comprehension; then with the measure of reading comprehension after 1 year, during fifth grade. Results showed that controlling for prior performance, verbal WM and fluid intelligence significantly predicted reading comprehension after 1 year, whereas verbal STM and intelligence mindset did not make a significant contribution. These results indicate that when jointly considered, a higher level of verbal WM and fluid intelligence in fourth grade is related to a better performance in reading comprehension in fifth grade. Possible explanations and implications of these results are discussed.

Role of verbal working memory in rapid procedural acquisition of a choice response task

How quickly are instructions for a task translated into an effective task-set? If declarative working memory (dWM) is used to maintain a task's S-R rules until practice compiles them adequately into procedural memory, variables that affect retrieval from dWM should influence task performance while it is still dependent on dWM. Participants were trained on a series of 6-choice RT tasks, with a 1:1 mapping from object pictures to keys. In Experiments 1 and 2, an instruction phase — presentation of the S-R rules one by one —was followed by test trials. The phonological similarity of the objects' names significantly affected performance only during the first few encounters with the stimuli. Serial position effects were also consistent with retrieval from verbal dWM during those early trials. In Experiment 3, instruction onon the S-R rules was omitted, so participants had to learn the S-R mappings by trial and error alone; the effect of phonological similarity lasted longer, but still disappeared after a dozen encounters with each stimulus. Experiment 4 showed that instructions and just four trials of practice per S-R rule were sufficient to form a persisting representation of the S-R rules robust enough to interfere with later acquisition of a competing S-R rule after several minutes spent acquiring other task-sets. An effective and lasting task-set is rapidly compiled into procedural memory through instruction and early feedback; verbal dWM plays little role thereafter.

Verbal working memory and co-speech gesture processing

Multimodal discourse requires an assembly of cognitive processes that are uniquely recruited for language comprehension in social contexts. In this study, we investigated the role of verbal working memory for the online integration of speech and iconic gestures. Participants memorized and rehearsed a series of auditorily presented digits in low (one digit) or high (four digits) memory load conditions. To observe how verbal working memory load impacts online discourse comprehension, ERPs were recorded while participants watched discourse videos containing either congruent or incongruent speech-gesture combinations during the maintenance portion of the memory task. While expected speech-gesture congruity effects were found in the low memory load condition, high memory load trials elicited enhanced frontal positivities that indicated a unique interaction between online speech-gesture integration and the availability of verbal working memory resources. This work contributes to an understanding of discourse comprehension by demonstrating that language processing in a multimodal context is subject to the relationship between cognitive resource availability and the degree of controlled processing required for task performance. We suggest that verbal working memory is less important for speech-gesture integration than it is for mediating speech processing under high task demands.

The role of verbal working memory in L2 sentence comprehension

AbstractConsiderable variability has been observed in sentence comprehension abilities in both native speakers and second language (L2) learner populations. While it has long been established that, in native speakers, this variability is closely linked to individual differences (IDs) in verbal working memory (vWM), previous research on the role of vWM in L2 sentence comprehension has produced mixed results. Moreover, there is an accumulating body of evidence demonstrating that the relationship between vWM and native language comprehension abilities is mediated by language experience. However, to our knowledge, until now, no attempt has been made to integrate language experience measures into the vWM-L2 sentence comprehension relationship. The goal of the present study is twofold: (1) to determine whether and to what extent vWM – as gauged by a reading span (RSPAN) task – correlates with IDs in two proxy estimates of L2 experience and (2) to investigate the effects of vWM on L2 comprehension of three different types of complex sentences. Thirty-four German advanced learners of English participated in this study. Significant positive correlations were found between the RSPAN scores and both proxy estimates of L2 experience. Mixed-effects modeling revealed that vWM exerted a significant effect on L2 sentence comprehension that was not modulated by sentence type. Taken together, these results provide additional evidence in support of the involvement of vWM in L2 sentence comprehension and, to our knowledge, first evidence for the contribution of L2 experience to RSPAN task performance.

Effects of Aquatic Motor Intervention on Verbal Working Memory and Brain Activity—A Pilot Study

ABSTRACTAquatic motor activity (AMA) has been reported to affect motor and cognitive abilities. However, the neural mechanisms that may mediate this relationship have never been explored. The traditional functions of the cerebellum include involvement in coordination and balance. Recent studies have shown cerebellar activity during verbal working memory (VWM) tasks.The purpose of this study was to examine the effects of AMA on VWM and changes in cerebellar activity. Twenty‐four subjects were allocated to 1 month of AMA, on‐land motor activity or nonmotor activity intervention. We examined the effects of intervention on VWM ability using the digit span task. Using magnetoencephalography, we measured changes in alpha power.Our results demonstrate that the AMA significantly improved VWM. Moreover, improved VWM was positively correlated with increased right cerebellar alpha power.These results support previous studies regarding the cerebellar region's role in VWM, and demonstrate that VWM can be improved by AMA.

Verbal working memory and early literacy acquisition: do ELLs allocate resources similar to their typical monolingual peers or monolingual children with SLI?

ABSTRACT The role of verbal working memory (VWM) in early language and literacy development among typical and atypical monolingual children exposed to different orthographies is well established. Less is known how English Language Learners (ELLs) allocate their VWM resources in early stages of literacy acquisition in English (L2). This study examined the role of phonological (PM) and working memory (WM) in L2 decoding, sight word recognition and spelling among ELLs attending kindergarten in an urban Title I school. The results of ELLs’ assessments across cognitive and linguistic reading pre-requisites were compared to the assessments on the same measures of typical and specific language impaired (SLI) monolingual peers. Despite decreased vocabulary and lower phonological awareness (PA) skills ELLs did not differ from typical monolingual peers on VWM skills and early literacy outcomes, but outperformed SLIs. However, ELLs relied exclusively on PM for decoding and spelling, which differed from typical monolingual peers. These results provide important information regarding L2 language and early literacy development among Spanish-speaking ELLs, and should help to conceptualize the educational strategies for supporting ELLs based on their L1 structure. Measure of PM may be discriminating criteria between ELLs and SLIs, as poor PM is an established marker for SLI.

Right Lateral Cerebellum Represents Linguistic Predictability.

Mounting evidence indicates that posterolateral portions of the cerebellum (right Crus I/II) contribute to language processing, but the nature of this role remains unclear. Based on a well-supported theory of cerebellar motor function, which ascribes to the cerebellum a role in short-term prediction through internal modeling, we hypothesize that right cerebellar Crus I/II supports prediction of upcoming sentence content. We tested this hypothesis using event-related fMRI in male and female human subjects by manipulating the predictability of written sentences. Our design controlled for motor planning and execution, as well as for linguistic features and working memory load; it also allowed separation of the prediction interval from the presentation of the final sentence item. In addition, three further fMRI tasks captured semantic, phonological, and orthographic processing to shed light on the nature of the information processed. As hypothesized, activity in right posterolateral cerebellum correlated with the predictability of the upcoming target word. This cerebellar region also responded to prediction error during the outcome of the trial. Further, this region was engaged in phonological, but not semantic or orthographic, processing. This is the first imaging study to demonstrate a right cerebellar contribution in language comprehension independently from motor, cognitive, and linguistic confounds. These results complement our work using other methodologies showing cerebellar engagement in linguistic prediction and suggest that internal modeling of phonological representations aids language production and comprehension.SIGNIFICANCE STATEMENT The cerebellum is traditionally seen as a motor structure that allows for smooth movement by predicting upcoming signals. However, the cerebellum is also consistently implicated in nonmotor functions such as language and working memory. Using fMRI, we identify a cerebellar area that is active when words are predicted and when these predictions are violated. This area is active in a separate task that requires phonological processing, but not in tasks that require semantic or visuospatial processing. Our results support the idea of prediction as a unifying cerebellar function in motor and nonmotor domains. We provide new insights by linking the cerebellar role in prediction to its role in verbal working memory, suggesting that these predictions involve phonological processing.

Impaired reasoning and problem-solving in individuals with language impairment due to aphasia or language delay.

The precise nature of the relationship between language and thought is an intriguing and challenging area of inquiry for scientists across many disciplines. In the realm of neuropsychology, research has investigated the inter-dependence of language and thought by testing individuals with compromised language abilities and observing whether performance in other cognitive domains is diminished. One group of such individuals is patients with aphasia who have an impairment in speech and language arising from a brain injury, such as a stroke. Our previous research has shown that the degree of language impairment in these individuals is strongly associated with the degree of impairment on complex reasoning tasks, such as the Wisconsin Card Sorting Task (WCST) and Raven’s Matrices. In the current study, we present new data from a large group of individuals with aphasia that show a dissociation in performance between putatively non-verbal tasks on the Wechsler Adult Intelligence Scale (WAIS) that require differing degrees of reasoning (Picture Completion vs. Picture Arrangement tasks). We also present an update and replication of our previous findings with the WCST showing that individuals with the most profound core language deficits (i.e., impaired comprehension and disordered language output) are particularly impaired on problem-solving tasks. In the second part of the paper, we present findings from a neurologically intact individual known as “Chelsea” who was not exposed to language due to an unaddressed hearing loss that was present since birth. At the age of 32, she was fitted with hearing aids and exposed to spoken and signed language for the first time, but she was only able to acquire a limited language capacity. Chelsea was tested on a series of standardized neuropsychological measures, including reasoning and problem-solving tasks. She was able to perform well on a number of visuospatial tasks but was disproportionately impaired on tasks that required reasoning, such as Raven’s Matrices and the WAIS Picture Arrangement task. Together, these findings suggest that language supports complex reasoning, possibly due to the facilitative role of verbal working memory and inner speech in higher mental processes.

Direct evidence for the causal role of the left supplementary motor area in working memory: A preliminary study

Working memory is defined as active short-term memory nvolved in purpose-oriented tasks [1]. It plays an essential role n activities of daily living and social life, such as conversation, eading, and calculation. Previous functional magnetic resonance maging (MRI) studies have reported activation in some brain egionsduringa language-relatedN-back task that evaluatedworkng memory; these regions include the dorsolateral prefrontal ortex, anterior cingulate cortex, Broca’s area, supramarginal gyrus, uperior parietal lobule, and supplementary motor area (SMA) [2]. lthough several studies involving human brain mapping have ndicated that short-term memory could be subserved by several rain regions, including the perisylvian cortex, superior frontal yrus, and fornix, there is no direct evidence that the SMA plays a ole in working memory in the human brain [3–6]. Here, we report hat the left SMA plays a role in verbal working memory and the sefulness of the intraoperative 2-back task for evaluatingworking emory during awake surgery.

Sentence processing and verbal working memory in a white-matter-disconnection patient

The Arcuate Fasciculus/Superior Longitudinal Fasciculus (AF/SLF) is the white-matter bundle that connects posterior superior temporal and inferior frontal cortex. Its causal functional role in sentence processing and verbal working memory is currently under debate. While impairments of sentence processing and verbal working memory often co-occur in patients suffering from AF/SLF damage, it is unclear whether these impairments result from shared white-matter damage to the verbal-working-memory network. The present study sought to specify the behavioral consequences of focal AF/SLF damage for sentence processing and verbal working memory, which were assessed in a single patient suffering from a cleft-like lesion spanning the deep left superior temporal gyrus, sparing most surrounding gray matter. While tractography suggests that the ventral fronto-temporal white-matter bundle is intact in this patient, the AF/SLF was not visible to tractography. In line with the hypothesis that the AF/SLF is causally involved in sentence processing, the patient׳s performance was selectively impaired on sentences that jointly involve both complex word orders and long word-storage intervals. However, the patient was unimpaired on sentences that only involved long word-storage intervals without involving complex word orders. On the contrary, the patient performed generally worse than a control group across standard verbal-working-memory tests. We conclude that the AF/SLF not only plays a causal role in sentence processing, linking regions of the left dorsal inferior frontal gyrus to the temporo-parietal region, but moreover plays a crucial role in verbal working memory, linking regions of the left ventral inferior frontal gyrus to the left temporo-parietal region. Together, the specific sentence-processing impairment and the more general verbal-working-memory impairment may imply that the AF/SLF subserves both sentence processing and verbal working memory, possibly pointing to the AF and SLF respectively supporting each.

Investigating the Role of Verbal Working Memory in Young Children's Sentence Comprehension

This study considers the role of verbal working memory in sentence comprehension in typically developing English‐speaking children. Fifty‐six (N = 56) children aged 4;0–6;6 completed a test of language comprehension that contained sentences which varied in complexity, standardized tests of vocabulary and nonverbal intelligence, and three tests of memory that measured the three verbal components of Baddeley's model of Working Memory (WM): the phonological loop, the episodic buffer, and the central executive. The results showed that children experienced most difficulty comprehending sentences that contained noncanonical word order (passives and object relative clauses). A series of linear mixed effects models were run to analyze the contribution of each component of WM to sentence comprehension. In contrast to most previous studies, the measure of the central executive did not predict comprehension accuracy. A canonicity by episodic buffer interaction showed that the episodic buffer measure was positively associated with better performance on the noncanonical sentences. The results are discussed with reference to capacity‐limit and experience‐dependent approaches to language comprehension.

Left Inferior Frontal Activations Differentially Modulated by Scrambling in Ditransitive Sentences

In order to clarify the relationship among grammatical knowledge, processing components, and neural substrates in sentence comprehension, we used functional magnetic resonance imaging to investigate how brain activation is affected by two types of scrambling (short scrambling and middle scrambling) in ditransitive sentences in Japanese. Short scrambling and middle scrambling enhanced activation in the anterior and posterior left inferior frontal gyrus respectively. This finding accords with the view that the anterior left inferior frontal gyrus is involved in the automatic processing that establishes a dependency relation between a verb and its arguments, and the posterior left inferior frontal gyrus supports this kind of processing through its role in verbal working memory. This result is more congruent with a process-based approach to neural bases for sentence processing, which searches for neurological correlates of psycholinguistically defined processing components, than with a grammar-based approach, which probes neural networks with the assumption that major grammatical operations are neurologically individuated.

An Examination of the Associations Among Multiple Memory Systems, Past Tense, and Vocabulary in Typically Developing 5-Year-Old Children

Considerable research has investigated the role of verbal working memory in language development in children with and without language problems. Much less is currently known about the relationship between language and the declarative and procedural memory systems. This study examined whether these 2 memory systems were related to typically developing children's past tense and lexical knowledge. Fifty-eight typically developing children approximately 5 years of age completed a battery of linguistic and nonlinguistic tasks, including tests of vocabulary, past tense production, and procedural and declarative memory. The results showed that declarative and procedural memory were not correlated with either regular or irregular past tense use. A significant correlation was observed between declarative memory and vocabulary. The results of the study were not consistent with the view that the declarative and procedural memory systems support children's use of the regular and irregular past tense. However, evidence was found suggesting that declarative memory supports vocabulary in this age group.

Working memory influences on cross-language activation during bilingual lexical disambiguation

This study investigated the role of verbal working memory on bilingual lexical disambiguation. Spanish–English bilinguals read sentences that ended in either a cognate or noncognate homonym or a control word. Participants decided whether follow-up target words were related in meaning to the sentences. On critical trials, sentences biased the subordinate meaning of a homonym and were followed by targets related to the dominant meaning. Bilinguals with high span were faster at rejecting unrelated targets when the sentences ended in a homonym, whereas bilinguals with low span were slower. Furthermore, error rates for bilinguals with low span showed cognate inhibition, while bilinguals with high span showed no effects of cross-language activation. Results demonstrated that bilinguals with high span benefit from shared lexical codes whether these converge on to a single semantic representation (cognates) or not (homonyms). Conversely, bilinguals with low span showed inhibition from the competing lexical codes, even when they converge onto a single semantic representation.

Text comprehension in Chinese children: Relative contribution of verbal working memory, pseudoword reading, rapid automatized naming, and onset-rime phonological segmentation.

The present study examined the role of verbal working memory (memory span, tongue twister), 2-character Chinese pseudoword reading, rapid automatized naming (letters, numbers), and phonological segmentation (deletion of rimes and onsets) in inferential text comprehension in Chinese in 518 Chinese children in Hong Kong in Grades 3 to 5. It was hypothesized that verbal working memory, together with a small contribution from the other constructs, would explain individual variation in the children's text comprehension. Structural equation modeling and hierarchical multiple regression analyses generally upheld the hypotheses. Though Chinese pseudoword reading did not play an important mediating role in the effect of verbal working memory on text comprehension, verbal working memory had strong effects on pseudoword reading and text comprehension. The findings on the Chinese language support current Western literature as well as display the differential role of the constructs in Chinese reading comprehension.

The role of working memory in decoding emotions.

Decoding facial expressions of emotion is an important aspect of social communication that is often impaired following psychiatric or neurological illness. However, little is known of the cognitive components involved in perceiving emotional expressions. Three dual task studies explored the role of verbal working memory in decoding emotions. Concurrent working memory load substantially interfered with choosing which emotional label described a facial expression (Experiment 1). A key factor in the magnitude of interference was the number of emotion labels from which to choose (Experiment 2). In contrast the ability to decide that two faces represented the same emotion in a discrimination task was relatively unaffected by concurrent working memory load (Experiment 3). Different methods of assessing emotion perception make substantially different demands on working memory. Implications for clinical disorders which affect both working memory and emotion perception are considered.

Component skills of text comprehension in less competent Chinese comprehenders

The present study examined the role of verbal working memory (memory span and tongue-twister), two-character Chinese pseudoword reading (two tasks), rapid automatized naming (RAN) (letters and numbers), and phonological segmentation (deletion of rimes and onsets) in inferential text comprehension in Chinese in 31 less competent comprehenders compared with 37 reading comprehension control students and 23 chronological age controls. It was hypothesized that the target students would perform poorly on these cognitive and linguistic tasks as compared with their controls. Furthermore, verbal working memory and pseudoword reading would explain a considerable amount of individual variation in Chinese text comprehension. RAN would have a nonsignificant role in text comprehension. Structural equation analyses and hierarchical multiple regression analyses generally upheld these hypotheses. Our findings support current literature of the role of verbal working memory in reading comprehension found in English. The results, however, suggest differential role of the constructs and the tasks in reading comprehension and provide some answers for comprehension impairment in Chinese students.

Cerebellar contributions to episodic memory encoding as revealed by fMRI

Event-related functional Magnetic Resonance Imaging (fMRI) allows for the comparison of hemodynamic responses evoked by items that are remembered in a subsequent memory task vs. items that are forgotten. In this way, brain regions that assumingly contribute to successful memory encoding have been identified, including the left inferior prefrontal cortex (LIPC) and the medial temporal lobe. Although a cerebellar involvement in verbal working memory is well-established, a contribution of the cerebellum to episodic long-term encoding has only sporadically been described, and mechanisms underlying cerebellar memory effects are unclear. We conducted a typical incidental verbal memory fMRI experiment with three different encoding tasks varying the depth of semantic processing. Slice positioning allowed for the coverage of the entire cerebellum. We observed a significant subsequent memory effect within the superior and posterior right cerebellar hemisphere that was task independent. Additionally, we found a different area within the superior right cerebellum displaying a memory effect specifically for semantically processed words and a bilateral cerebellar activation specifically associated with encoding success only for a non-semantic task. Our results suggest that besides its known role in verbal working memory, the cerebellum contributes to episodic long-term encoding and should therefore be considered in future fMRI studies dealing with episodic memory.